1. Field of the Invention
The invention relates to a drilling device having a drive motor that sets a tool in rotation, a feed motor that axially displaces the tool and a supply unit that supplies the drive motor and the feed motor with power.
2. Discussion of Relevant Art
From DE 94 02 360 U1 a drilling device is known, which is used to bore holes in a wide variety of types of ground. Associated with the drive motor of said drilling device is a load sensor, the output of which is connected to a control input of a quantity limiter and/or current limiter and/or pressure limiter and/or voltage limiter, which is inserted into a supply line for the feed motor. Overloading of the drive motor is avoided in that at a constant tool speed there is an automatic reduction of the tool feed force upon an increase of the tool torque.
It was then discovered that the fastest possible penetration of the tool into different types of ground is obtained when the tool feed force and the tool speed are each tuned to the ground conditions, i.e. to the hardness of the ground.